THE EFFECT OF SOME REAGENTS ON THE “FILTRATE FACTOR” (A WATER-SOLUBLE VITAMIN BELONGING TO THE VITAMIN B COMPLEX AND PREVENTING A DIETARY DERMATITIS IN CHICKS)

Abstract

Kline, Keenan, Elvehjem, and Hart (1) have described a syndrome produced in chicks by feeding a heated diet of natural foodstuffs.Elvehjem and Koehn (2) have described the preparation from liver of a concentrate which will prevent the syndrome.The concentrate was prepared from an aqueous extract of liver from which the flavins had been removed by adsorption on fullers' earth and filtration.It is proposed for the sake of brevity to refer in this communication to the factor present in the concentrate as the "filtrate factor," in reference to the method of preparation by its discoverers (1, 2).The name intentionally leaves in abeyance the question of the identity or non-identity of the factor with the rat factor vitamin Ba (3).It has been suggested by Stare (4) that the two factors may be identical, but Gyiirgy (3) reported vitamin Bg to be destroyed by visible light, while Elvehjem and Koehn (2) reported that the chick factor was not destroyed by exposure to light. EXPERIMENTAL Method of AssayThe care of the chicks, the production of the syndrome, and the method of scoring for intensity of symptoms have been previously described (5).It was found desirable to introduce the following modifications.1. Vitamin G (lactoflavin) was added to the diet in the form of a fullers' earth adsorbate of whey corresponding to 60 per cent of